1. First, have a shop that already converts well. Know the basics of ecommerce 101. Therefore you will be in a good position to maximise affiliate traffic.
2. Be the shop keeper! Don't try and mess being an affiliate too.
3. Lose the banner exchanges, top site links etc. It wastes your PR, sends your traffic away, loses the concentration of the visitor. (All covered in No.1)
4. Utilise descriptive, seo friendly, product names and descriptions. Product names should NOT be "White T-Shirt" etc. Descriptions should not include hyperlinks in them or prompts to shop on your website. Sell the product the customer is looking at.
5. Don't bother with itzy bitzy markups. At least $5 please.
6. Don't use CJ links in your custom shop which is prominently linked to from your premium shop.
7. Tag well!! Don't over tag with complete useless nonsense. Ignore the rubbish CafePress suggest and really home in on the markets your design will appeal to.
8. Use a special tag and let your affiliates know it. This makes fantastic, high quality landing pages that your affiliates can use.
9. Provide some way for your affiliates to contact you. Be there when they want something.
10. Keep making great designs! Announce them here and speak up when affiliates are looking.
11. When an affiliate posts a request with specific requirements, please read the post carefully and only post your designs that meets the requirements that the affiliate is looking for. This saves the affiliate from reading through numerous posts and clicking endless links that may not be what was requested, in order to find one design that meets the requirements.